CVE-2026-12327
Full vulnerability record from the local CVENow database.
Description
Memory safety bugs present in Firefox ESR 140.11, Thunderbird ESR 140.11, Firefox 151 and Thunderbird 151. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.
Severity
HIGH
CVSS score
8.1
(v3.1)
Vulnerability status
Analyzed
Source identifier
Published
2026-06-16 13:16:33.473000
Last modified
2026-10-26 12:10:00.130000
View original CVE JSON
{
"id": "CVE-2026-12327",
"sourceIdentifier": "[email protected]",
"published": "2026-06-16T13:16:33.473",
"lastModified": "2026-10-26T12:10:00.130",
"vulnStatus": "Analyzed",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "Memory safety bugs present in Firefox ESR 140.11, Thunderbird ESR 140.11, Firefox 151 and Thunderbird 151. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12."
},
{
"lang": "es",
"value": "Errores de seguridad de memoria presentes en Firefox ESR 140.11, Thunderbird ESR 140.11, Firefox 151 y Thunderbird 151. Algunos de estos errores mostraron evidencia de corrupción de memoria y presumimos que, con suficiente esfuerzo, algunos de estos podrían haber sido explotados para ejecutar código arbitrario. Esta vulnerabilidad fue corregida en Firefox 152, Firefox ESR 140.12, Thunderbird 152 y Thunderbird 140.12."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "Mozilla",
"product": "Firefox",
"versions": [
{
"version": "140.12",
"lessThanOrEqual": "140.*",
"versionType": "rpm",
"status": "unaffected"
},
{
"version": "152",
"lessThanOrEqual": "*",
"versionType": "rpm",
"status": "unaffected"
}
]
},
{
"vendor": "Mozilla",
"product": "Thunderbird",
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{
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"lessThanOrEqual": "140.*",
"versionType": "rpm",
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},
{
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"lessThanOrEqual": "*",
"versionType": "rpm",
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}
]
}
]
}
],
"metrics": {
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"baseScore": 8.1,
"baseSeverity": "HIGH",
"attackVector": "NETWORK",
"attackComplexity": "HIGH",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"availabilityImpact": "HIGH"
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"references": [
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"source": "[email protected]",
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}